Communion was no light topic for the reformers. That’s why I’ve enjoyed reading some of Calvin’s writings on the subject. While there is a heavy emphasis on personal examination prior to coming to the table, I enjoyed finding the assurance that even our self examination is to be found wanting and that, eventually, we just have to come in faith and receive the gift of God in the table. Despite our weakness, he bids us come. In The Manner of Celebrating the Lord’s Supper Calvin puts it this way (emphasis mine):
Next, let us not be ungrateful to the infinite goodness of our Saviour, who displays all his riches and blessings at this table, in order to dispense them to us; for, in giving himself to us, he bears testimony to us that all which he has is ours. Moreover, let us receive this sacrament as a pledge that the virtue of his death and passion is imputed to us for righteousness, just as if we had suffered it in our own persons. Let us not be so perverse as to keep back when Jesus Christ invites us so gently by his word; but while reflecting on the dignity of the precious gift which he gives us, let us present ourselves to him with ardent zeal, in order that he may make us capable of receiving him.
John Calvin and Henry Beveridge, Tracts Relating to the Reformation, Volume 2 (Bellingham, WA: Logos Research Systems, Inc., 2009), 121.